In this agarose gel electrophoresis, the lane indicated by the arrow represents a monoclonal immunoglobulin. Monoclonal paraproteins appear as sharp bands in the globulin area of the serum electrophoresis patterns. In this particular case, the patient was subsequently diagnosed with an immunoglobulin G (IgG) multiple myeloma.

A multiple myeloma is a malignant neoplasm of a single clone of plasma cells of the bone marrow. The most common monoclonal immunoglobulin in multiple myelomas is an IgG paraprotein.